This project investigates the etiologies of cardiac hemolytic anemia and possible medical therapies of this post-surgical complication. A group of patients has been characterized on the basis of hemolysis rate, valve function, ferrokinetics, and bone marrow iron stores. Selected patients are now being treated with a trial course of propranolol in an effort to decrease hemolysis rate, allowing the bone marrow to maintain the red cell mass at a more normal level.